Synchronizing clock system.



. C. E. LARRABEE.

SYNCHRONIZING CLOCK SYSTEM. APFUCATION man DEC. 12. 1918.

1,313,305, Patented Aug. 19, 1919.

CLINTON E. LABRABEE, 0F BINGHAMTON, NEW YORK.

SYN'CHRONIZING CLOCK SYSTEM.

Specification of Letters Patent.

Patented Aug. 19, 1919.

Application filed December 12, 1918. Serial No. 266,419.

To all whom it may concern:

Be it known that I, CLINTON E. LAnnA- BEE, a citizen of the United States, residing at Binghamton, in the county of Broome and State of New York, have invented certain new and useful Improvements in Synchronizing Clock Systems, of which the following is a full, clear, and exact, description.

The im'ention which forms the subjectmatterof my present application for Letters Patent is an improvement in synchronizing clock systems and involves a new form of master clock for use in an impulse-systerm or one in which any number of secondary clock mechanisms are operated by pcriodic impulses of current sent out by the master clock which in any known way advance, step by step, the hands of the secondaries.

Specifically stated the improvement is designed to provide the master clock with means for maintaining it substantially fully wound at all times; with means for sending at definiteperiods over the controllingline the current impulses that operate the secondary clock; with means that give an indication, audible or visual, the moment that the main or operative source of current fails, as it may do when an ordinary municipal or industrial lighting or power circuit is used as the source of supply, and with means for advancing at a relatively high rate the hands of the secondaries to a position of synchronism with the master clock when for any cause there has been an interruption in the current transmitted over the line so that the secondary clock has failed to receive the proper number of impulses to keep it in step with the hands of the master clock.

The means by which I have carried out my invention are not in themselves new, but I have combined them in certain new ways and relations which enable them to cooper ate in a novel manner to secure the results above stated. I may therefore refer to the accompanying drawing for a description of their nature, purpose and manner of com binat-ion. p

The figure of the annexed drawing shows the essential arrangement and construction of the devices in the master clock, the gear train, winding spring and other accessories of the clock being omitted, as these are or may be of the usual and well known construction. The secondary clock or clocks to be controlled by the master clock are also omitted from the illustration, as these may be of any known or usual construction.

The numeral 1 indicates a shaft, such as the arbor of a master clock of any known and desired construction, that is to say, any arbor therein which makes, say, one complete revolution in a iven time, preferably one minute. This ar r carries three circuit controllers, viz., a contact arm 2 in electrical contact with the shaft which cooperates with a flexible stationary contact arm 3 with which the arm makes periodic contact, in this case assumed to be once each minute; a second arm 4, in electrical contact with a sleeve 5 insulated from the shaft 1, and (:0- operating with a similar stationary arm 6 to make one contact each minute simultaneously with the contacts 2 and 3, and a third multiple contact 7 on a sleeve 8 insulated from the shaft 1 and cooperating with a stationary arm 9 and designed to make, say, ten contacts in a minute.

Brushes 10 connected with the main source of current supply bear on the sleeves 5 and 8 and thus connect contacts 4 and 7 with the said source, and a brush 11 connected with a local source of current bears on the shaft 1, and thus connects the arm 2 with such source. Connections from the arms 3, G and 9 are made by wires to the devices hereinafter described.

The clock contains three circuits, the current for two of which is furnished by a local battery or other convenient source 1Q,whilc that for the third or line circuit is supplied by any convenient source, such as a local or municipal plant represented by 13.

Normally the source 12 sends a current through the contact arms 2 and 3 once a minute over a local circuit formed by wires 14, 15, 16 and 17. This circuit includes the clock winding magnet 18, which operates to wind up the driving spring of the clock step by step, the specific means for this purpose not being shown, and an electro-niagnet 19 which operates through the instrumentality of a pawl 20 to move one of the ratchet wheels 21 of a differential gear one tooth or step for each impulse passing over the circuit.

At the same time, since the shaft 1 is rotating, a line impulse from the source 13 passes through the contacts 4 and 6 once a minute and at the same inst-ants as the impulses in the described local circuitand these impulses pass over wires 22, 23 and 26 to line, and 0 erate the secondary clocks. This part of t e circuit includes two contacts 24 and 25, which are normally in contact and an electro-magnet 27 which opcrates through a pawl 28 to turn the ratchet wheel 29 one tooth or step for each impulse passing, and in a direction opposite to that in which the ratchet wheel 21' rotates.

The ratchet wheels 21 and 29 are respectively fixed to the gears 30 of the differential, and as they are rotated normally in opposite directions by the two magnets 19 and 27 at the same rate, the intermediate floating gear 31, on a shaft 32, merely rotates about a fixed axis, but should one ratchet wheel rotate while the other remains stationary, or there should occur a difference in the rates, then the axis of the floating gear, as'represented by the shaft 32, will be moved in one direction or the other around the axis 34 of the ratchet wheels in the Well-known manner. This operation is illustrated diagrammatically only, and for purposes of this invention the shaft 32 is shown as carrying two rods or arms 35, cooperating with and adapted to control contacts 24 and 25 and also other contacts 36 and 37, and a third contact 38, immediately under contact 25,- in such manner that when the shaft 32.is moved clockwise, as it will be when ratchet wheel 29 stops rotating, the contact 25 will leave the contact 24, and come into engagement with contact 38, and contacts 36 and 37 will be permitted or caused to come together.

Normally, as has been stated, the relations of the parts are such that contacts 36 and 37 and contacts 25 and 38 are out of engagement; but contacts 24 and 25 are together, but should the main current fail for any cause then the downward movement of the shaft-32 closes contacts 36 and 37 and contacts 25 and 38. The closure of contacts 36 and 37 closes a circuit from battery 12 over wires 39 and 40, including an indicator 41, an alarm bell 42, or any other mechanism such as a switch to throw a reserve battery into the line. This calls the attention of the attendants to a source of trouble which they may take immediate steps'to correct.

When by such correction or other causes :he supply of main current is again renewed, the floating member of the differential will have been moved through a given arc, and contacts 25 and 38 are together while 24 and 25 are apart. The main current will therefore pass by wires 22 and 43 to the multiple contact arms 7, and through arms 7 and 9, at ten times the normal rate, over wire 44 to contact 38, and thence to line through contact 25, wire 26 and electro-magnet 27.

By this means the secondary clocks will be rapidly advanced and the ratchet wheel 29 correspondingly rotated until the floating member 31 is brought to its normal position,

contacts 36 and 37 separated, and contacts 24 and 25 closed, or in other words the lost impulses will be made up to the secondary clocks and they will be brought up into synchronism with the master clock. Thereafter, and until there is another interruption in the main supply of current the two magnet 19 and 27 will work in unison and the floating member 31 remain in its normal position.

The mechanical details of this system are not of the essence of the invention and may be Worked out in great variety by any one skilled in the art. All of the devices shown or which in practice it would be desirable to employ are well-known and used under similar conditions but for other purposes.

What I claim as my invention is 1. In a master clock for synchronizing systems, the combination of a movable member, a local circuit under the control of the clock for imparting movement at a given rate to said movable member, a second movable member, a main circuit connection, also under the control of the clock, for imparting a like movement to said second member in exact unison with the first, and means adapted to be brought into operation by the failure ofthe main source of current and the departure of the two members from unison to give a signal.

2. In a master clock for synchronizing systems, the combination of a movable member, a local circuit under the control of the clock for imparting movement at a given rate to said movable member, a second movable member, a main circuit connection, also under the control of the clock, for imparting a like movement to said second member in exact unison with the first, means adapted to be shifted by the failure of the main current to move its member to an extent proportional to the departure from unison of the two members, a circuit connection moving such member step by step when energized by such impulses, a line circuit, a circuit-closer therein also operated by the clock train for sending to line current impulses at the same instants that the impulses are sent through the local circuit, an electro-magnet in the line circuit, a second movable member moved thereby step by step, and means operated by a variation in the rate of movement of the said two members for controlling the action of indicating or other devices.

4. In a master clock for synchronizing systems, the combination of a local circuit, a circuit-controller therein operated by the clock train for sending periodic impulses over the local circuit, an electro-magnet in the local circuit, and a differential gear one member of which is moved step by step by the local current impulses, a line circuitcontroller therein also operated by theclock train for sending impulses to line at the same instants that impulses are sent over the local circuit, a magnet in said circuit operating step by step the second member of the differential, a oating member in said differential, and indicating or controlling mechanism operated thereby when its position is displaced by any variation in the relative rates of movement of the two members of said differential.

5. In a master clock for synchronizing systems, the combination of a local circuit, a circuit-controller therein operated by the master clock for sending periodic impulses over said local circuit, a magnet in the local circuit, a differential gear one member of which is moved step by step by the local circuit impulses, a, line circuit, a circuit-controller therein also operated by the clock train for sending impulses to line at the same instants that impulses are sent over the local circuit, a magnet in the line circuit operating step by step the second member of the differential, a floating member in said differential adapted to be shifted in position by a variation in the relative rat-es of movement of the two members of the differential, and a si al device closed for operation by and during the period of displacement of the floating member.

6. In a master clock for synchronizing systems, the combination of a local circuit, a circuit controller therein operated by the master clock for sending periodic impulses over said local circuit, va magnet in said local circuit, a difl'erential gear one member of which is moved step by step by the local circuit impulses, a line circuit, a circuit-controller therein also operated by the clock train for sending impulses to line at the same instants that impulses are sent over the local circuit, a magnet in the line circuit operating step by step in an opposite direction the second member of the differential, a floating member in said differential adapted to be shifted in position by a variation in the relative rates of movement of the two members and to an extent proportional to their displacement, and a relatively rapid circuit closer in the main circuit adapted to be thrown into operation by and during the period in which the floating member is shifted from normal position to bring said member into normal position.

In testimony whereof I hereunto affix my signature.

CLINTON E. LARRABEE. 

